Blood pressure measuring device

Abstract

A noninvasive blood pressure measuring device includes display means which may be digital readouts, a sphygmomanometer or other similar means, a compression cuff, a first flexible tube, a second flexible tube, an air leak valve and monitoring, control and display circuitry. Within the compression cuff is an inflatable bladder which extends in a longitudinal direction for substantially the entire length of the compression cuff. The monitoring, control and display circuitry includes a piezoelectric crystal assembly which provides electrical signals in response to air pressure levels and changes within the first flexible tube. The first tube connects this piezoelectric crystal assembly with the compression cuff and the second tube has a hand pump at one end for inflating the bladder. The air leak valve is in line with the first tube and the air leak valve has a continuously open air escape aperture of a size which corresponds to a predetermined leak rate proportional to the pressure in the bladder. When a sphygmomanometer is incorporated as part of the display means, a branch tube connects the first flexible tube to the sphygmomanometer and a pair of light-emitting diodes mounted to the dial face of the sphygmomanometer indicate when sphygmomanometer readings should be taken for systolic and diastolic conditions. When digital readouts and a microprocessor are used as part of the monitoring, control and display circuitry, data such as, for example, heart rate and mean pressure in addition to systolic and diastolic pressures are automatically presented and may be read directly.

Dependencies are inferred from the claim text.